One single refinery, Carbon Green Bioenergy, outside Lake Odessa, Mich., helps tell the story. "This was built as a 40 million plant," says the owner, Mitch Miller. "We're running at 50 million gallons a year. So, we have not reduced capacity at all."

The demand, Dwyer reports, isn't because of E85.

It's because conventional gasoline contains 10 percent ethanol. Last year, for the first time, more corn was used to produce ethanol than as livestock feed. Of course, livestock farmers aren't happy, since their cost for feed has gone up.